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Soil surface moisture is one of the key parameters for describing the hydrological state and assessing the potential availability of water for irrigated plants. Because the radar backscattering coefficient is sensitive to soil moisture, the application of Sentinel-1 data may support soil surface moisture mapping at high spatial resolution by detecting spatial and temporal changes at the field scale for precision irrigation management. This mapping is required to control soil water erosion and preferential water flow to improve irrigation water efficiency and minimise negative impacts on surface and ground water bodies. Direct observations of soil surface moisture (5-cm thickness) were performed at an experimental plot in the study site of the All-Russian Scientific Research Institute of Irrigated Agriculture, near the village Vodnyy, Volgograd region. Soil surface moisture retrieval from Sentinel-1 was performed at the same location. A second set of soil surface moisture was calculated for the soil sampling sites using the permittivity model, based on the estimates of soil surface characteristics: a) reflectivity, obtained by the neural network method from Sentinel-1 observations; b) roughness, obtained from the geodata of the stereoscopic survey with unmanned aerial vehicle Phantom 4 Pro. The raster set of soil surface moisture geodata was obtained based on the reflectivity geodata raster set to solve the inverse problem using a permittivity model that considers the soil texture of the experimental plot. The determination coefficient (0.948) and standard deviation (2.04%) were obtained by comparing both sets of soil moisture point geodata taken from the same soil sampling sites. The values confirmed a satisfactory linear correlation between the directly measured and indirectly modelled sets. A comparison of the two sets of geodata indicated a satisfactory reproduction of the first set by the second set. As a result, the developed method can be considered as the scientific and methodological basis of the new technology of soil surface moisture monitoring by radar, which is one of the basic characteristics used in precision irrigation management.

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We present the results of magnetic force microscopy investigations of domain structures in multilayer [Co (0.5 nm)/Pt (1 nm)]5 thin film structures (denoted hereafter as Co/Pt) modified by additional Co capping layers and by ion irradiation. It is demonstrated that a Co capping layer essentially changes the domain structure and decreases the threshold of magnetization reversal, due to the formation of noncollinear magnetization in Co/Pt. It is shown that local irradiation with a focused He⁺ ion beam enables the formation of regions with decreased easy-axis anisotropy (magnetic bubbles) that have the inverse magnetization direction in the demagnetized state of Co/Pt. The experimental results demonstrate that the magnetic bubbles can be switched using a probe of a magnetic force microscope. The possible application of these effects for the development of magnetic logic and data storage systems is discussed.

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Ribosomes of eukaryotic cells contain four rRNA's (28S, 18S, 5,8S and 5S) and about 80 ribosomal proteins (RP). Whereas the patterns of evolution and chromosomal location of rRNA genes are studied rather extensively in many taxonomic groups, there is only scarce information about evolution of genes coding ribosomal proteins. To obtain more information about evolution of ribosomal protein genes, the study of the nucleotide sequences and chromosomal location of rp111 gene was carried out in 12 species of the genus Chironomus. Characteristics of intra- and interspecific variability of this gene have been obtained and a high percenatage of identity has been shown between nucleotide sequences of different species from the Chironomus. FISH analysis has shown that ribosomal protein gene rp111 is located in a single site (region 25f), near centromere of the arm B. No variations in the number of sites and chromosomal position of the gene were observed in the karyotypes of the studied chironomid species indicating the evolutionary conservation of the chromosomal region where rp111 is located. We have established that the number and location of rp111 gene in chromosomal karyotypes of studied chironomid species do not coincide with the number and positions of 5,8S rRNA gene. The data obtained allow to conclude that the evolution of nucleotide sequences and chromosomal location of rp111 and 5,8S rRNA genes in genomes of Chironomus species occurred independently.

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An approach to derive relationships for defining land degradation and desertification risk and developing appropriate tools for assessing the effectiveness of the various land management practices using indicators is presented in the present paper. In order to investigate which indicators are most effective in assessing the level of desertification risk, a total of 70 candidate indicators was selected providing information for the biophysical environment, socio-economic conditions, and land management characteristics. The indicators were defined in 1,672 field sites located in 17 study areas in the Mediterranean region, Eastern Europe, Latin America, Africa, and Asia. Based on an existing geo-referenced database, classes were designated for each indicator and a sensitivity score to desertification was assigned to each class based on existing research. The obtained data were analyzed for the various processes of land degradation at farm level. The derived methodology was assessed using independent indicators, such as the measured soil erosion rate, and the organic matter content of the soil. Based on regression analyses, the collected indicator set can be reduced to a number of effective indicators ranging from 8 to 17 in the various processes of land degradation. Among the most important indicators identified as affecting land degradation and desertification risk were rain seasonality, slope gradient, plant cover, rate of land abandonment, land-use intensity, and the level of policy implementation.

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Indicator-based approaches are often used to monitor land degradation and desertification from the global to the very local scale. However, there is still little agreement on which indicators may best reflect both status and trends of these phenomena. In this study, various processes of land degradation and desertification have been analyzed in 17 study sites around the world using a wide set of biophysical and socioeconomic indicators. The database described earlier in this issue by Kosmas and others (Environ Manage, 2013) for defining desertification risk was further analyzed to define the most important indicators related to the following degradation processes: water erosion in various land uses, tillage erosion, soil salinization, water stress, forest fires, and overgrazing. A correlation analysis was applied to the selected indicators in order to identify the most important variables contributing to each land degradation process. The analysis indicates that the most important indicators are: (i) rain seasonality affecting water erosion, water stress, and forest fires, (ii) slope gradient affecting water erosion, tillage erosion and water stress, and (iii) water scarcity soil salinization, water stress, and forest fires. Implementation of existing regulations or policies concerned with resources development and environmental sustainability was identified as the most important indicator of land protection.

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The data on the cytogenetic monitoring of the Usmansky and Khrenovskoy autochthonic pine stands (Voronezh Region) allow their status to be rated satisfactory. The indices of the mitotic and nucleolar activity as well as of abnormal mitosis were within the normal variation range for Scotch pine. However, the occurrence of micronuclei (less than 1%) points to pathological processes starting in the stands, which necessitates urgent measures for the conservation of the Usmansky and Khrenovskoy Forests as valuable gene sources.

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Biomineralization, the biologically controlled formation of mineral deposits, is of widespread importance in biology, medicine, and engineering. Mineralized structures are found in most metazoan phyla and often have supportive, protective, or feeding functions. Among deuterostomes, only echinoderms and vertebrates produce extensive biomineralized structures. Although skeletons appeared independently in these two groups, ancestors of the vertebrates and echinoderms may have utilized similar components of a shared genetic "toolkit" to carry out biomineralization. The present study had two goals. First, we sought to expand our understanding of the proteins involved in biomineralization in the sea urchin, a powerful model system for analyzing the basic cellular and molecular mechanisms that underlie this process. Second, we sought to shed light on the possible evolutionary relationships between biomineralization in echinoderms and vertebrates. We used several computational methods to survey the genome of the purple sea urchin Strongylocentrotus purpuratus for gene products involved in biomineralization. Our analysis has greatly expanded the collection of biomineralization-related proteins. We have found that these proteins are often members of small families encoded by genes that are clustered in the genome. Most of the proteins are sea urchin-specific; that is, they have no apparent homologues in other invertebrate deuterostomes or vertebrates. Similarly, many of the vertebrate proteins that mediate mineral deposition do not have counterparts in the S. purpuratus genome. Our findings therefore reveal substantial differences in the primary sequences of proteins that mediate biomineral formation in echinoderms and vertebrates, possibly reflecting loose constraints on the primary structures of the proteins involved. On the other hand, certain cellular and molecular processes associated with earlier events in skeletogenesis appear similar in echinoderms and vertebrates, leaving open the possibility of deeper evolutionary relationships.

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The purpose of the study was to determine the level of thrombus precursor protein (TrP) in patients with acute coronary syndrome (ACS). Twenty-six patients with ACS and anginal pain experienced during 2 to 12 hours (7.2 +/- 1.3 hours), admitted to cardiological intensive care unit, were enrolled in the study. Five ml of blood were sampled from a cubital vein of all the patients during the phase of the most intensive pain. TrP blood levels were measured with ELISA, Enzyme-Linked Immunoadsorbent Assay. The control group consisted of 29 healthy volunteers and 22 patients with stable exertional stenocardia. A significant increase in TpR (7.2 +/- 1.45 mcg/ml) was noted in the ACS patients as early as during the first 6 hours, vs. the healthy controls (1.01 +/- 0.12 mcg/ml) and the patients with stable stenocardia (1.21 +/- 0.06 mcg/ml), p < 0.01. A high level of TrP in the ACS patients could be noted earlier than a diagnostically significant increase in creatine phosphokinase level. No direct correlation was observed between the TrP level and the dynamics of such indices of the procoagulatory hemocoagulation chain as fibrinogen, prothrombin index, and active partial thromboplastin time. The results of the study demonstrate that the measurement of TrP level is highly informative when the intensity of intravascular blood coagulation in ACS patients is to be evaluated, which can be used to clarify indications to anticoagulation therapy. The enzyme immune method of TrP detection in the plasma of ACS patients can be recommended for clinical application.

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The purpose of the study was to measure the blood level of thrombus precursor protein (TpP), a soluble fibrin monomer, in patients with stable exertional angina (SEA) and healthy people. The study included the examination of 33 patients with SEA (functional class II and III) and 29 practically healthy volunteers (control group). The detection of TpP in blood plasma was performed by solid-phase immune-enzyme analysis ("sandwich" type) using commercial diagnosticum "Kit" ("ABS", USA) and a microplate reader "IEMS Analyzer\Dispenser, with automatic result calculation in "Logistic fif" mode. TpP level in patients with SEA on the average was slightly higher than in control group, but the difference was not significant. TpP blood level was independent of the patients' gender, age, angina functional class and an old myocardial infarction. TpP blood level in patients with SEA depended on the duration of the illness, and proved to be significantly higher (compared with that in control group) in patients with SEA during the first 5 years of the illness, i.e. at early stages of CHD. Solid-phase immune-enzyme analysis ("sandwich" type) is a highly informative and affordable clinical method. TpP level in patients with SEA on the average was slightly higher than in healthy people (1.21 +/- 0.06 mkg/ml and 1.01 +/- 0.12 mkg/ml, respectively), but the difference was significant only in patients during the first 5 years of having SEA (1.41 +/- 0.11 mkg/ml).

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Microarray technology makes it possible to simultaneously study the expression of thousands of genes during a single experiment. We have developed an information system, ArrayDB, to manage and analyse large-scale expression data. The underlying relational database was designed to allow flexibility in the nature and structure of data input and also in the generation of standard or customized reports through a web-browser interface. ArrayDB provides varied options for data retrieval and analysis tools that should facilitate the interpretation of complex hybridization results. A sampling of ArrayDB storage, retrieval and analysis capabilities is available (www.nhgri.nih.gov/DIR/LCG/15K/HTML/ ), along with information on a set of approximately 15,000 genes used to fabricate several widely used microarrays. Information stored in ArrayDB is used to provide integrated gene expression reports by linking array target sequences with NCBI's Entrez retrieval system, UniGene and KEGG pathway views. The integration of external information resources is essential in interpreting intrinsic patterns and relationships in large-scale gene expression data.

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The major drawback of subtractive cDNA libraries is that the original disproportion in concentrations of different types of transcripts is preserved. This usually makes the isolation of specific rare transcripts extremely difficult. To overcome this difficulty, we propose a strategy that introduces the equalization of concentrations (normalization) of specific transcripts during the subtractive process. This makes possible obtaining both rare and highly abundant transcripts in the resulting subtracted library. This technique has been applied for isolation of transcripts activated upon induction of Jurkat cells by phytohemaglutinin and phorbol 12-myristate 13-acetate. Six novel up-regulated sequences belonging to a low-abundance class of transcripts have been obtained.

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The present status of genomic DNA subtraction techniques is reviewed. The advantages and disadvantages of the widely-used methods of genome subtraction are discussed. Using the kinetic model of subtractive hybridization developed by us previously (Sverdlov and Ermolaeva, 1993; Sverdlov and Ermolaeva, 1994), the application of genome subtraction to various problems is analyzed. It is concluded that the technique should be further advanced based on subtraction of single-stranded DNAs. This strategy would enable one to efficiently extract target sequences omitting the stage of genome simplification.

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A novel theory of subtractive hybridization including (or based on) the kinetic model of this process was proposed. A computer program modeling the process of subtraction was developed. Basing on the theory, a novel method of subtractive hybridization was proposed allowing routine comparison of genomes and products of genome expression. The method was applied to studies of the genetic mechanisms of embryogenesis, regeneration, cell differentiation and tumor transformation.

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We report on a new software tool, SUBTRACT, which allows the analysis of the possible strategies for an experiment based on a mathematical model of subtractive hybridization. The program helps the experimenter choose the optimal strategy and conditions for performing the reaction. The program allows the modeling of cDNA and genomic subtraction for different types of target DNA. SUBTRACT offers a friendly interface for the investigation of the dynamics of the process of subtractive hybridization, and for modifying different parameters and initial conditions. SUBTRACT allows the user to plot the values of interesting quantities as a function of the reaction time. The program runs under the Unix operating system on Sun-compatible computers.

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The human genome contains multiple copies of sequences related to the HERV-K family of endogenous retroviruses, homologous to the B-type mouse mammary tumour virus. A DNA fragment closely resembling an HERV-K long tandem repeat (LTR) was detected in a library of hncDNA clones enriched for sequences from human chromosome 19. Sites showing homology to the sequence of this fragment have been identified on human chromosome 19 by hybridization to previously mapped chromosome 19 cosmids. Thus the distribution of LTR sequences on a specific human chromosome has been mapped for the first time. We estimate the total number of such sites on human chromosome 19 to be at least 110. Many of these sites are located in the vicinity of known genes. The precise localizations (to specific cosmids) of LTR-homologous sequences on chromosome 19 can serve as a reference source and will automatically provide further insight into LTR-gene relationships as new genes are mapped onto the chromosome.

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A simple technique for preparation of libraries of the human chromosome specific transcribed sequences is developed. It uses hnRNA from human-rodent hybrid cell lines containing particular human chromosomes or their fragments and includes three stages: (i) reverse transcription of the hnRNA with Alu-specific primers directing the transcription beyond the Alu-repeats to flanking non-repetitive sequences of the chromosome; (ii) nested primer PCR strategy with specifically designed primers; (iii) direct selective cloning of the second-stage nested primer PCR products. An arrayed hncDNA library was prepared from a hybrid cell line containing chromosome 19 and fragments of 22 and X chromosomes. The library contains around 98% of human-specific transcribed sequences. Sequences of 52 human-specific, according to PCR analysis, clones differed from each other and had no close analogs in the EMBL Data Bank. Of 17 clones assigned to certain human chromosomes, 9 belonged to chromosome 19, 5 to chromosome 22 and 3 to chromosome X. Some of the human specific clones contained repetitive elements scattered over different human chromosomes. Clones from hncDNA libraries are useful as STSs/ESTs, as probes for detecting full-size genes in genomic libraries, for RFLP analysis and for identification of chromosome specific cDNAs.

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A new technique based on Alu-PCR amplification of hn-RNA is described for the extraction of human-specific transcribed sequences from a hybrid cell line. Arrayed library of hn-cDNA was constructed and characterized by sequencing about 80 individual clones. A high enrichment by human-specific sequences (about 95%) was demonstrated.

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A theoretical analysis of kinetics of two subtractive cDNA hybridizations has been carried out: hybridisation of an excess of denatured double-stranded cDNA (driver) with denatured double-stranded cDNA (tracer) containing some sequences (targets) missing from the driver, and hybridisation of denatured double-stranded tracer with denatured double-stranded driver unable to be renatured. Our calculations show that the first strategy requires several rounds of hybridisation for sufficient enrichment of tracer with target sequences of the low-abundant mRNA: in the first round the renatured fraction is removed, and in subsequent rounds the remaining single-stranded fraction cDNA is used and renatured fraction is collected. The second strategy makes it possible to sufficiently enrich non-reassociated fraction of tracer with minor fractions of target sequences in a single round of subtractive hybridisation.

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